Astron. Astrophys. Suppl. Ser. 144, 523-532

Adaptive optics imaging of P Cygni in H$_{\alpha }$

O. Chesneau¹ - M. Roche² - A. Boccaletti³ - L. Abe¹ - C. Moutou⁴ - F. Charbonnier⁵ - C. Aime² - H. Lantéri² - F. Vakili¹

Send offprint request: O. Chesneau

Correspondence to: chesneau@astro.umontreal.ca

1 - Observatoire de la Côte d'Azur, Département Fresnel, GI2T, F-06460 Saint Vallier de Thiey, France
2 - UMR 6525 Astrophysique, Université de Nice Sophia Antipolis Parc Valrose, F-06108 Nice Cedex 2, France
3 - Collège de France, 11 Pl. M. Berthelot, F-75321 Paris, France
4 - European Southern Observatory, Alonso de Cordoba 3107, Santiago, Chile
5 - Office National d'Études et de Recherches Aérospatiales, Département d'Optique Théorique et Appliquée Imagerie Haute Résolution - Optique Adaptative, 29 Av. de la Division Leclerc, F-92320 Chatillon, France

Received January 10; accepted March 20, 2000

Abstract:

We obtained H$_{\alpha }$ diffraction limited data of the LBV star P Cyg using the ONERA Adaptive Optics (AO) facility BOA at the OHP 1.52 m telescope on October 1997. Taking P Cyg and the reference star 59 Cyg AO long exposures, we find that P Cyg clearly exhibits a large and diffuse intensity distribution compared to the 59 Cyg's point-like source. A deconvolution of P Cyg using 59 Cyg as the Point Spread Function was performed by means of the Richardson-Lucy algorithm. P Cyg clearly appears as an unresolved star surrounded by a clumped envelope. The reconstructed image of P Cyg is compared to similar spatial resolution maps obtained from radio aperture synthesis imaging. We put independent constraints on the physics of P Cyg which agree well with radio results. We discuss future possibilities to constrain the wind structure of P Cyg by using multi-resolution imaging, coronagraphy and long baseline interferometry to trace back its evolutionary status.

Key words: star: P Cyg -- stars: winds, imaging, circumstellar matter -- instrumentation: adaptive optics